Note: The billing party has sole responsibility
for CPT coding. Any questions regarding coding should be directed
to the payer being billed. The CPT codes provided by GML are
based on AMA guidelines and are for informational purposes only.

Factor V Leiden is a common cause of inherited thrombophilia. The R506Q mutation leads to resistance of degradation of the factor V protein by activated protein C (APC). Heterozygotes, or individuals who have one copy of the mutation, carry a 5- to 10-fold increased risk of venous thrombosis. Homozygotes, or individuals who have two copies of the mutation, carry at 50- to 100-fold increased risk.